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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Identificação de novos alérgenos de pólen do cajueiro (Anacardium occidentale L.) para auxílio no diagnóstico e futura otimização do tratamento / Identification of novel allergens of cashew pollen

Figo, Daniele Danella 28 June 2017 (has links)
A polinose é uma rinite alérgica sazonal que acontece pela sensibilização por pólens. Possui periodicidade anual, repetindo-se os sintomas sempre na mesma época do ano. Clinicamente, é caracterizada por rinoconjuntivite e/ou asma brônquica. A imunoterapia alérgeno-específica é o único tratamento capaz de modificar a evolução natural da doença, porém, depende fundamentalmente da correta identificação do alérgeno responsável. Diante disso e do número de pacientes que procuram o Ambulatório de Alergia da Universidade de Fortaleza com manifestações alérgicas exacerbadas na época de floração do cajueiro, o objetivo deste estudo foi produzir um extrato protéico a partir do pólen do cajueiro e identificar os alérgenos ainda não estudados presentes neste pólen. Doze pacientes residentes em Fortaleza, Nordeste do país, foram selecionados com base na história de rinite alérgica persistente e agravamento dos sintomas no momento da floração do cajueiro. Foi selecionado outro grupo com rinite alérgica que vive na mesma região, entretanto não apresenta relação clínica com a época de floração. Além disso, foram incluídos 5 indivíduos não-atópicos e expostos ao cajueiro como grupo controle. O soro desses pacientes foi testado em Western Blot 1D e 2D (WB) e as proteínas selecionadas foram submetidas à espectrometria de massas para identificação. Os epitopos foram preditos in silico pesquisando sequências detectadas por massa contra bases de dados de epítopos já conhecidos. Foi possível identificar alguns homólogos de alérgenos de outros pólens, como isoflavona redutase (Bet v 6), beta-1,3-glucanase (Ole e 9), proteína de choque térmico 70kDa (Cor a 10), além de outras proteínas que podem representar novos alergénios, tais como aminociclase, glutamina sintetase, fosfoglucomutase, ?-1,4-glucano-proteína-sintase, factor de alongamento 2 e biotina carboxilase, entre outros. A predição de epítopos revelou a possibilidade de reatividade cruzada com outros alérgenos de pólen conhecidos, tais como Phl p 4, Mal d 1, além de outros aeroalérgenos que também apareceram. Esta é a primeira descrição da alergia ao pólen do caju mostrando a reatividade específica de IgE no soros dos pacientes. A caracterização imunológica e estrutural de novos alérgenos, além de auxiliar no diagnóstico e tratamento de alergias não descritas, oferece ferramentas para prever epítopos e produzir moléculas hipoalergênicas nesta era da medicina de precisão / Pollinosis is a seasonal allergic rhinitis that develops due to pollens sensitization. Symptoms are manifested always in the same period of the year. Clinically, it is characterized by rhinoconjunctivitis and/or asthma. Allergen-specific immunotherapy is the only available treatment that can modify the natural course of the disease, however, it relies on the correct identification of the triggering allergen. Considering this and the number of patients attending the Allergy Clinic at University of Fortaleza with exacerbation of allergic symptoms during cashew flowering period, the aim of this study was to produce a protein extract from cashew tree pollen and identify the allergens not yet studied. Twelve patients living in Fortaleza, Northeast of country, were selected based on history of persistent allergic rhinitis and aggravation of symptoms at the time of cashew tree flowering. Another group living in the same region with allergic rhinitis without clinical relation with the flowering season was selected. Also 5 non-atopic subjects exposed to cashew tree were selected as a control group. The serum of these patients was tested for 1D and 2D Western Blotting (WB) and selected proteins were submitted to mass spectrometry for identification. Epitopes were predicted by in silico search comparing detected sequences against epitope databases. It was possible to identify some homologs of allergens from other pollens such as isoflavone reductase (Bet v 6), beta-1,3-glucanase (Ole e 9), heat shock protein 70kDa (Cor a 10), besides other proteins that might represent novel allergens, such aminociclase, glutamina sintetase, phosphoglucomutase, alpha-1,4-glucan-protein-synthase, elongation factor 2 and biotin carboxylase among others. The epitope prediction revealed the possibility of cross-reactivity with other known pollen allergens such as Phl p 4, Mal d 1 and other aeroallergens also appeared. This is the first description of cashew pollen allergy showing specific IgE reactivity of patients\' sera. The immunological and structural characterization of new allergens, besides aiding the diagnosis and treatment of non-described allergies, offers tools for predicting epitopes and producing hypoallergenic molecules in this era of precision medicine
52

Annexin A1 as an endogenous regulator of mast cell degranulation

Sinniah, Ajantha January 2015 (has links)
Annexin A1 (Anx-A1) is a 37kDa protein that is secreted by some cells in response to glucocorticoids (GCs) and which mediates several of their acute anti-inflammatory effects. In addition to GCs, ‘mast cell stabilising’ cromones such as nedocromil also mobilise Anx-A1 by promoting its phosphorylation by protein kinase C (PKC) and hence its secretion, which explains their acute efficacy as anti-allergic agents. This thesis addresses a fundamental aspect of Anx-A1 in the actions of anti-allergic drugs. In this study, anti-allergic drugs such as H1 antagonists, mast cell stabilisers and ‘dual action’ drugs were first tested for their ability to enhance Anx-A1 phosphorylation in a model system using U937 cells. Biochemical and immuno-fluorescent techniques were used to study the mechanisms by which these drugs suppress mediator release from cord blood derived mast cells (CDMCs) and murine bone-marrow derived mast cells (BMDMCs) from wild type and Anx-A1 null-mice. This thesis suggest that PKC activation is crucial for Anx-A1 export in mast cells and nedocromil in the presence of dexamethasone, prolongs the duration of PKC activation and subsequently phosphorylation, externalisation and release of Anx-A1 from CDMCs. The ability of nedocromil to inhibit β-hexosaminidase, tryptase, histamine and PGD2 release are dependent on Anx-A1 in CDMCs. Interestingly, ketotifen, a ‘dual action’ drug possesses a similar pharmacological profile to nedocromil, but not promethazine, which does not act through the Anx-A1 release. Strong evidence supports the notion that the mechanisms of action of nedocromil are modulated by Anx-A1, thus the possibility that FPR2 might be involved in the acute actions of nedocromil was tested. Nedocromil inhibits the release of PGD2 through the activation of FPR2 but not the inhibition of histamine release. A possible explanation for this finding could be that Anx-A1 might be interacting with other FPR family members to exert the histamine inhibitory effects. Although only a small subset of the downstream intracellular signaling pathway of MAPK was tested, the results indicate that Anx-A1 differentially regulates the activation of p38 and JNK in CDMCs treated with nedocromil. These findings indicate a novel model system in which Anx-A1 mediates the pharmacological actions of anti-allergic drugs and thus has an important role in preventing the mast cell degranulation.
53

New mechanisms of regulation of mast cell activation

Endoh, Ikuko, Medical Sciences, Faculty of Medicine, UNSW January 2008 (has links)
Mast cells (MCs) play a central role in inflammation by releasing mediators following activation. S100A8 and S100A9 are abundantly expressed in inflammatory sites such as asthmatic lung, sunburnt skin and atherosclerosis where MCs are involved in pathogenesis; roles of S100A8 in MC function are undetermined. The aims of this thesis were to determine effects of S100A8 on MC activation, particularly provoked by IgE and UVB. Initially, effects of UVB on MC activation were investigated as detailed functions were unclear. Cord blood-derived human mast cells (CBMCs) were treated in vitro with varying doses of UVB and production of multiple cytokines and viability investigated. UVB exposure selectively increased levels of IL-8 (CXCL8), and to a less extent IL-1β, but not eight other cytokines tested. New protein synthesis partially contributed and IL-8 production was p38 MAPK-dependent. UVB dose-dependently induced MC apoptosis indicating a potential regulatory mechanism of MC function. The ability of recombinant S100A8, S100A9 or S100A8/9 heterodimer to modulate IgE/antigen (DNP/anti-DNP)-mediated activation of a murine MC line, and of bone marrow-derived (mBM) MC activation was determined. The S100s did not directly induce degranulation or induce IL-6. S100A8 significantly inhibited DNP/anti-DNP-provoked degranulation, and IL-6 and TNF mRNA and protein induction. S100A8 did not alter FcεRIα expression. S100A9 was less effective; and the S100A8/9 complex was also suppressive. S100A8 only weakly suppressed non-specific MC degranulation. Mutation of Cys41 in S100A8 negated its suppressive activity. Because S100A8 scavenges oxidants via this reactive Cys residue, we propose that this may mediate its ability to downmodulate IgE-dependent MC responses. Similar to the thiol scavenger N-acetyl-L-cysteine, S100A8 but not the Ala41 mutant, attenuated DNP/anti-DNP-provoked LAT phosphorylation. However, the disulfide-bonded S100A8 dimer and S100A8 containing a sulfinamide bond between Cys41 and Lys34/35 also reduced MC activation, indicating an additional pathway(s). S100A8 did not suppress antigen/IgE-induced responses of CBMC possibly because these may not truly reflect fullymature human tissue MCs. S100A8 did not alter UVB-induced IL-8 release by CBMCs, or affect apoptosis. Murine S100A8 may have anti-inflammatory properties by regulating MC activation in an activator-specific manner, at least partially by scavenging ROS to suppress intracellular signalling.
54

The prevalence of allergic diseases in primary school in Yu-Li and the common allergens in Eastern Taiwan.

Huang, Chun-fong 20 June 2006 (has links)
The prevalence of childhood allergic diseases has been increasing in Taiwan. In Taipei area, according to the surveillance of Hsieh KH, the prevalence rate of childhood asthma increased from 1.3% in 1974 to 10.79% in 1994. The other allergic diseases, such as allergic rhinitis, atopic dermatitis and urticaria , have been also increasing in Taipei, Taichung and Tainan city by a serious studies in Western Taiwan. There is no any report of childhood allergic diseases in Eastern Taiwan till now. So, we want to analyze the prevalence of childhood allergic diseases and the common allergens in Eastern Taiwan. From Nov. 2002 to Oct. 2004, all of the primary school children in Yu-Li town in Hualien county were included in this study. (total 2058 children of 12 school). All of them were surveyed with pediatric allergic diseases questionnaire (asthma, allergic rhinitis, atopic dermatitis and urticaria). After the survey, the suspected allergic cases were analyzed for their hypersensitivity to the common allergens by allergen screening test and specific IgE exam of Pharmacia CAP system. 1816 children completed the questionnaire (completive rate 88.24%) and 688 (37.88%) children were suspected to have allergic diseases. 151 (8.87%) asthma¡F448 (24.67%) allergic rhinitis¡F70 (3.85%) atopic dermatitis¡F65 (3.58%) urticaria. A total of 623 suspected allergic cases were analyzed for their hypersensitivity to the common allergens. The common allergens were also analyzed. 87.7% allergic to D. pteronyssinus (Dp) ; 83.9% Blomia tropicalis (Bt) ; 35.0% German cockroach; 16.0% Dog dander; 7.5% Cat dander; 8.0% Candida albicans; 11.2% Bermuda grass; 38.6% shrimp; 33.1% crab; 26.6% milk; 14.3% egg white; 6.7% peanuts; 6.1% Cod fish; 5.4% Wheat; 4.7% Soya bean. The prevalence of childhood allergic diseases in Eastern Taiwan is lower than Western Taiwan. The different envelopment and living type may be the major reasons. From this study, we also suggest that Blomia tropicalis (Bt) should be included in the common aeroallergy analysis in Eastern Taiwan.
55

Measurement of nerve growth factor in induced sputum and exhaled breath condensate

Nwiloh, Victor Maduabuchi 01 June 2006 (has links)
Several tests are available for evaluation of respiratory disorders but most of them are invasive and associated with some risk or patient discomfort. Examples include bronchoscopy (bronchoalveolar lavage, BAL) [1], venopuncture [2] and sputum induction [3]. Noninvasive sampling of nongaseous substances contained in expired air, collected as exhaled breath condensate (EBC) has been used to detect inflammatory markers and by-products including nitric oxide and arachidonic acid metabolites and proteins [4]. Nerve growth factor (NGF) is a protein that has been implicated in neurogenic airway inflammation and this pilot study aimed to develop a non-invasive approach for evaluation of allergic airway inflammatory disease by measuring and comparing levels of NGF in the induced sputum and EBC of ten (10) asthmatics and ten (10) non-asthmatics.Though twenty (20) subjects were sampled, an unexpected event due to a defective NGF kit inadvertently resulted in an unsuccessful analysis of fifteen (15) sets of specimen (6 non-asthmatics and 9 asthmatics), limiting the study.This study is significant because occupational lung diseases are the number one work-related illness in the United States and occupational asthma is the most common form [9]. Toluene diisocyanate (TDI) is the commonest cause of occupational asthma and workers exposed to TDI vapor may develop inflammatory conditions including asthma, rhinitis and nasal irritation [7].Results: NGF was detected and measured only in sputum, with a mean NGF level of 210 (210-210, range 0) in asthmatics and 164 (7-280, range 273) in non-asthmatics. Nonetheless, we failed to reject the null hypothesis (number 3).Conclusion: This limited study did not have adequate power (power 11%) due to the small sample size and thus lacks internal validity. Further studies are needed using a larger sample size.
56

Environmental and immunological factors associated with allergic disease in children

Tomičić, Sara January 2008 (has links)
Background: Allergic diseases are characterised by dysregulated immune responses. The first manifestation of the atopic phenotype is often food allergy, with symptoms like eczema. Food allergy in children is generally outgrown before 3 years of age, but a temporary food elimination diet is often advocated. The prevalence of allergic diseases has increased in affluent countries during the last decades, possibly as a consequence of a changed lifestyle leading to decreased microbial load. Aim: To investigate humoral, mucosal and cell-mediated immunity in association to allergy and allergy development in young children and relate this to environmental factors. Subjects: Two cohorts of children were investigated; 1) Children from countries with high (Sweden) and low (Estonia) prevalence of allergy that were followed prospectively from birth to 5 years of age. 2) Infants with eczema and suspected food allergy that were followed prospectively to 4 ½ years of age. Methods: Endotoxin levels were analysed in house dust samples. Antibodies were measured in serum and saliva samples with ELISA. Food allergen induced cytokine responses were analysed in mononuclear cells. Results: The microbial load, delineated as endotoxin levels, was higher in house dust from Estonia than Sweden and was, in Swedish children, inversely associated with sensitisation and clinical symptoms of allergy. The decreased microbial load in Sweden may have an impact on mucosal immune responses as different IgA antibody patterns were observed in Sweden and Estonian children with much lower secretory (S)IgA antibody levels and high proportion of non-SIgA, i.e. IgA antibodies lacking the secretory component, in the Swedish children. Moreover, low levels of SIgA were associated with clinical symptoms in sensitised children. High IgG4 antibody levels to food allergens during infancy were associated with faster tolerance development in food allergic children. Cytokine responses by mononuclear cells after allergen stimulation was upregulated with age in children with prolonged food allergy, but not in children who develop tolerance before 4 ½ years of age, possibly because of the prolonged elimination diet in the former group. Summary: Reduced microbial exposure in affluent countries may affect the mucosal immune responses during infancy, possibly resulting in an increased risk of developing allergic disease. High levels of IgG4 antibodies during infancy are associated with faster achievement of tolerance in food allergic children. Allergen elimination during infancy may result in a dysfunctional cytokine response.
57

Untersuchungen zum allergenen Potential der luftgetragenen Algen Stichococcus bacillaris, Tetracystis aeria und Xanthonema montanum

Sommer, Nadine 28 January 2014 (has links) (PDF)
Die Allergische Rhinitis als Allergie vom Typ I (Soforttyp) ist nicht nur in Deutschland und Europa weit verbreitet, sondern eine weltweit auftretende Erkrankung. Als Verursacher werden neben bereits bekannten Aeroallergenen wie Hausstaubmilben, Gräser oder Pollen auch luftgetragene Algen diskutiert, die als möglichen Mechanismus über eine T-Zell-abhängige Stimulation Antigen-bindender B-Zellen zur IgE-Produktion führen. Diese Arbeit befasst sich mit der Untersuchung des allergenen Potentials der luftgetragenen Algenspezies S. bacillaris, T. aeria und X. montanum. Dafür wurden mittels direkter und indirekter Sandwich-ELISA-Verfahren Seren von Patienten mit der Diagnose Allergische Rhinitis oder Idiopathische Rhinitis auf enthaltene IgE-Antikörper getestet, die spezifisch an festphasengebundene Algenproteine binden. Des Weiteren wurden Kompetitionstestungen zur Untersuchung der Kreuzhemmbarkeit der drei Algen sowie SDS-Gelelektrophoresen und Western Blots zur Bestimmung der Molmasse der Algenproteine und zum Nachweis der Spezifität des algenbindenden IgEs durchgeführt. Die Ergebnisse belegen, dass die getesteten Algenproteine in der Lage sind, eine entsprechende Immunantwort mit IgE-Produktion auszulösen. Diese neue Gruppe von Allergenen konnte hinsichtlich der Entstehung einer Allergie vom Soforttyp und der damit verbundenen klinischen Bedeutung bewertet werden.
58

New mechanisms of regulation of mast cell activation

Endoh, Ikuko, Medical Sciences, Faculty of Medicine, UNSW January 2008 (has links)
Mast cells (MCs) play a central role in inflammation by releasing mediators following activation. S100A8 and S100A9 are abundantly expressed in inflammatory sites such as asthmatic lung, sunburnt skin and atherosclerosis where MCs are involved in pathogenesis; roles of S100A8 in MC function are undetermined. The aims of this thesis were to determine effects of S100A8 on MC activation, particularly provoked by IgE and UVB. Initially, effects of UVB on MC activation were investigated as detailed functions were unclear. Cord blood-derived human mast cells (CBMCs) were treated in vitro with varying doses of UVB and production of multiple cytokines and viability investigated. UVB exposure selectively increased levels of IL-8 (CXCL8), and to a less extent IL-1β, but not eight other cytokines tested. New protein synthesis partially contributed and IL-8 production was p38 MAPK-dependent. UVB dose-dependently induced MC apoptosis indicating a potential regulatory mechanism of MC function. The ability of recombinant S100A8, S100A9 or S100A8/9 heterodimer to modulate IgE/antigen (DNP/anti-DNP)-mediated activation of a murine MC line, and of bone marrow-derived (mBM) MC activation was determined. The S100s did not directly induce degranulation or induce IL-6. S100A8 significantly inhibited DNP/anti-DNP-provoked degranulation, and IL-6 and TNF mRNA and protein induction. S100A8 did not alter FcεRIα expression. S100A9 was less effective; and the S100A8/9 complex was also suppressive. S100A8 only weakly suppressed non-specific MC degranulation. Mutation of Cys41 in S100A8 negated its suppressive activity. Because S100A8 scavenges oxidants via this reactive Cys residue, we propose that this may mediate its ability to downmodulate IgE-dependent MC responses. Similar to the thiol scavenger N-acetyl-L-cysteine, S100A8 but not the Ala41 mutant, attenuated DNP/anti-DNP-provoked LAT phosphorylation. However, the disulfide-bonded S100A8 dimer and S100A8 containing a sulfinamide bond between Cys41 and Lys34/35 also reduced MC activation, indicating an additional pathway(s). S100A8 did not suppress antigen/IgE-induced responses of CBMC possibly because these may not truly reflect fullymature human tissue MCs. S100A8 did not alter UVB-induced IL-8 release by CBMCs, or affect apoptosis. Murine S100A8 may have anti-inflammatory properties by regulating MC activation in an activator-specific manner, at least partially by scavenging ROS to suppress intracellular signalling.
59

Rhinostereometry and laser doppler flowmetry : simultaneous measurements of inflammation and steroid effects in normal and allergic human nasal mucosa /

Grudemo, Hans, January 1900 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst. / Härtill 6 uppsatser.
60

Study of serotonin, innervation and sensory neuropeptides in allergic contact dermatitis /

El-Nour, Husameldin, January 2005 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2005. / Härtill 5 uppsatser.

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